Release 4.7 arch/x86/power/cpu.c

/*
 * Suspend support specific for i386/x86-64.
 *
 * Distribute under GPLv2
 *
 * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl>
 * Copyright (c) 2002 Pavel Machek <pavel@ucw.cz>
 * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
 */

#include <linux/suspend.h>
#include <linux/export.h>
#include <linux/smp.h>
#include <linux/perf_event.h>

#include <asm/pgtable.h>
#include <asm/proto.h>
#include <asm/mtrr.h>
#include <asm/page.h>
#include <asm/mce.h>
#include <asm/suspend.h>
#include <asm/fpu/internal.h>
#include <asm/debugreg.h>
#include <asm/cpu.h>
#include <asm/mmu_context.h>
#include <linux/dmi.h>

#ifdef CONFIG_X86_32

__visible unsigned long saved_context_ebx;


__visible unsigned long saved_context_esp, saved_context_ebp;


__visible unsigned long saved_context_esi, saved_context_edi;

__visible unsigned long saved_context_eflags;
#endif

struct saved_context saved_context;



static void msr_save_context(struct saved_context *ctxt)
{
	struct saved_msr *msr = ctxt->saved_msrs.array;
	struct saved_msr *end = msr + ctxt->saved_msrs.num;

	while (msr < end) {
		msr->valid = !rdmsrl_safe(msr->info.msr_no, &msr->info.reg.q);
		msr++;
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
chen yu
chen yu
69
100.00%
1
100.00%
Total
69
100.00%
1
100.00%



static void msr_restore_context(struct saved_context *ctxt)
{
	struct saved_msr *msr = ctxt->saved_msrs.array;
	struct saved_msr *end = msr + ctxt->saved_msrs.num;

	while (msr < end) {
		if (msr->valid)
			wrmsrl(msr->info.msr_no, msr->info.reg.q);
		msr++;
	}
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
chen yu
chen yu
69
100.00%
1
100.00%
Total
69
100.00%
1
100.00%

/**
 *      __save_processor_state - save CPU registers before creating a
 *              hibernation image and before restoring the memory state from it
 *      @ctxt - structure to store the registers contents in
 *
 *      NOTE: If there is a CPU register the modification of which by the
 *      boot kernel (ie. the kernel used for loading the hibernation image)
 *      might affect the operations of the restored target kernel (ie. the one
 *      saved in the hibernation image), then its contents must be saved by this
 *      function.  In other words, if kernel A is hibernated and different
 *      kernel B is used for loading the hibernation image into memory, the
 *      kernel A's __save_processor_state() function must save all registers
 *      needed by kernel A, so that it can operate correctly after the resume
 *      regardless of what kernel B does in the meantime.
 */


static void __save_processor_state(struct saved_context *ctxt)
{
#ifdef CONFIG_X86_32
	mtrr_save_fixed_ranges(NULL);
#endif
	kernel_fpu_begin();

	/*
         * descriptor tables
         */
#ifdef CONFIG_X86_32
	store_idt(&ctxt->idt);
#else
/* CONFIG_X86_64 */
	store_idt((struct desc_ptr *)&ctxt->idt_limit);
#endif
	/*
         * We save it here, but restore it only in the hibernate case.
         * For ACPI S3 resume, this is loaded via 'early_gdt_desc' in 64-bit
         * mode in "secondary_startup_64". In 32-bit mode it is done via
         * 'pmode_gdt' in wakeup_start.
         */
	ctxt->gdt_desc.size = GDT_SIZE - 1;
	ctxt->gdt_desc.address = (unsigned long)get_cpu_gdt_table(smp_processor_id());

	store_tr(ctxt->tr);

	/* XMM0..XMM15 should be handled by kernel_fpu_begin(). */
	/*
         * segment registers
         */
#ifdef CONFIG_X86_32
	savesegment(es, ctxt->es);
	savesegment(fs, ctxt->fs);
	savesegment(gs, ctxt->gs);
	savesegment(ss, ctxt->ss);
#else
/* CONFIG_X86_64 */
	asm volatile ("movw %%ds, %0" : "=m" (ctxt->ds));
	asm volatile ("movw %%es, %0" : "=m" (ctxt->es));
	asm volatile ("movw %%fs, %0" : "=m" (ctxt->fs));
	asm volatile ("movw %%gs, %0" : "=m" (ctxt->gs));
	asm volatile ("movw %%ss, %0" : "=m" (ctxt->ss));

	rdmsrl(MSR_FS_BASE, ctxt->fs_base);
	rdmsrl(MSR_GS_BASE, ctxt->gs_base);
	rdmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
	mtrr_save_fixed_ranges(NULL);

	rdmsrl(MSR_EFER, ctxt->efer);
#endif

	/*
         * control registers
         */
	ctxt->cr0 = read_cr0();
	ctxt->cr2 = read_cr2();
	ctxt->cr3 = read_cr3();
	ctxt->cr4 = __read_cr4_safe();
#ifdef CONFIG_X86_64
	ctxt->cr8 = read_cr8();
#endif
	ctxt->misc_enable_saved = !rdmsrl_safe(MSR_IA32_MISC_ENABLE,
					       &ctxt->misc_enable);
	msr_save_context(ctxt);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
rafael j. wysocki
rafael j. wysocki
123
49.00%
1
16.67%
sergio luis
sergio luis
77
30.68%
1
16.67%
konrad rzeszutek wilk
konrad rzeszutek wilk
27
10.76%
1
16.67%
ondrej zary
ondrej zary
15
5.98%
1
16.67%
chen yu
chen yu
5
1.99%
1
16.67%
andy lutomirski
andy lutomirski
4
1.59%
1
16.67%
Total
251
100.00%
6
100.00%

/* Needed by apm.c */


void save_processor_state(void)
{
	__save_processor_state(&saved_context);
	x86_platform.save_sched_clock_state();
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
rafael j. wysocki
rafael j. wysocki
13
72.22%
1
33.33%
suresh siddha
suresh siddha
3
16.67%
1
33.33%
marcelo tosatti
marcelo tosatti
2
11.11%
1
33.33%
Total
18
100.00%
3
100.00%

#ifdef CONFIG_X86_32

EXPORT_SYMBOL(save_processor_state);
#endif



static void do_fpu_end(void)
{
	/*
         * Restore FPU regs if necessary.
         */
	kernel_fpu_end();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
rafael j. wysocki
rafael j. wysocki
11
91.67%
1
50.00%
sergio luis
sergio luis
1
8.33%
1
50.00%
Total
12
100.00%
2
100.00%



static void fix_processor_context(void)
{
	int cpu = smp_processor_id();
	struct tss_struct *t = &per_cpu(cpu_tss, cpu);
#ifdef CONFIG_X86_64
	struct desc_struct *desc = get_cpu_gdt_table(cpu);
	tss_desc tss;
#endif
	set_tss_desc(cpu, t);	/*
                                 * This just modifies memory; should not be
                                 * necessary. But... This is necessary, because
                                 * 386 hardware has concept of busy TSS or some
                                 * similar stupidity.
                                 */

#ifdef CONFIG_X86_64
	memcpy(&tss, &desc[GDT_ENTRY_TSS], sizeof(tss_desc));
	tss.type = 0x9; /* The available 64-bit TSS (see AMD vol 2, pg 91 */
	write_gdt_entry(desc, GDT_ENTRY_TSS, &tss, DESC_TSS);

	syscall_init();				/* This sets MSR_*STAR and related */
#endif
	load_TR_desc();				/* This does ltr */
	load_mm_ldt(current->active_mm);	/* This does lldt */

	fpu__resume_cpu();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
sergio luis
sergio luis
62
54.87%
1
20.00%
konrad rzeszutek wilk
konrad rzeszutek wilk
46
40.71%
1
20.00%
ingo molnar
ingo molnar
3
2.65%
1
20.00%
andy lutomirski
andy lutomirski
2
1.77%
2
40.00%
Total
113
100.00%
5
100.00%

/**
 *      __restore_processor_state - restore the contents of CPU registers saved
 *              by __save_processor_state()
 *      @ctxt - structure to load the registers contents from
 */


static void notrace __restore_processor_state(struct saved_context *ctxt)
{
	if (ctxt->misc_enable_saved)
		wrmsrl(MSR_IA32_MISC_ENABLE, ctxt->misc_enable);
	/*
         * control registers
         */
	/* cr4 was introduced in the Pentium CPU */
#ifdef CONFIG_X86_32
	if (ctxt->cr4)
		__write_cr4(ctxt->cr4);
#else
/* CONFIG X86_64 */
	wrmsrl(MSR_EFER, ctxt->efer);
	write_cr8(ctxt->cr8);
	__write_cr4(ctxt->cr4);
#endif
	write_cr3(ctxt->cr3);
	write_cr2(ctxt->cr2);
	write_cr0(ctxt->cr0);

	/*
         * now restore the descriptor tables to their proper values
         * ltr is done i fix_processor_context().
         */
#ifdef CONFIG_X86_32
	load_idt(&ctxt->idt);
#else
/* CONFIG_X86_64 */
	load_idt((const struct desc_ptr *)&ctxt->idt_limit);
#endif

	/*
         * segment registers
         */
#ifdef CONFIG_X86_32
	loadsegment(es, ctxt->es);
	loadsegment(fs, ctxt->fs);
	loadsegment(gs, ctxt->gs);
	loadsegment(ss, ctxt->ss);

	/*
         * sysenter MSRs
         */
	if (boot_cpu_has(X86_FEATURE_SEP))
		enable_sep_cpu();
#else
/* CONFIG_X86_64 */
	asm volatile ("movw %0, %%ds" :: "r" (ctxt->ds));
	asm volatile ("movw %0, %%es" :: "r" (ctxt->es));
	asm volatile ("movw %0, %%fs" :: "r" (ctxt->fs));
	load_gs_index(ctxt->gs);
	asm volatile ("movw %0, %%ss" :: "r" (ctxt->ss));

	wrmsrl(MSR_FS_BASE, ctxt->fs_base);
	wrmsrl(MSR_GS_BASE, ctxt->gs_base);
	wrmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base);
#endif

	fix_processor_context();

	do_fpu_end();
	x86_platform.restore_sched_clock_state();
	mtrr_bp_restore();
	perf_restore_debug_store();
	msr_restore_context(ctxt);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
rafael j. wysocki
rafael j. wysocki
125
50.20%
1
11.11%
sergio luis
sergio luis
92
36.95%
1
11.11%
ondrej zary
ondrej zary
15
6.02%
1
11.11%
chen yu
chen yu
5
2.01%
1
11.11%
marcelo tosatti
marcelo tosatti
5
2.01%
1
11.11%
stephane eranian
stephane eranian
3
1.20%
1
11.11%
andy lutomirski
andy lutomirski
2
0.80%
1
11.11%
steven rostedt
steven rostedt
1
0.40%
1
11.11%
suresh siddha
suresh siddha
1
0.40%
1
11.11%
Total
249
100.00%
9
100.00%

/* Needed by apm.c */


void notrace restore_processor_state(void)
{
	__restore_processor_state(&saved_context);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
rafael j. wysocki
rafael j. wysocki
13
92.86%
1
50.00%
steven rostedt
steven rostedt
1
7.14%
1
50.00%
Total
14
100.00%
2
100.00%

#ifdef CONFIG_X86_32

EXPORT_SYMBOL(restore_processor_state);
#endif

/*
 * When bsp_check() is called in hibernate and suspend, cpu hotplug
 * is disabled already. So it's unnessary to handle race condition between
 * cpumask query and cpu hotplug.
 */


static int bsp_check(void)
{
	if (cpumask_first(cpu_online_mask) != 0) {
		pr_warn("CPU0 is offline.\n");
		return -ENODEV;
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
fenghua yu
fenghua yu
31
100.00%
1
100.00%
Total
31
100.00%
1
100.00%



static int bsp_pm_callback(struct notifier_block *nb, unsigned long action,
			   void *ptr)
{
	int ret = 0;

	switch (action) {
	case PM_SUSPEND_PREPARE:
	case PM_HIBERNATION_PREPARE:
		ret = bsp_check();
		break;
#ifdef CONFIG_DEBUG_HOTPLUG_CPU0
	case PM_RESTORE_PREPARE:
		/*
                 * When system resumes from hibernation, online CPU0 because
                 * 1. it's required for resume and
                 * 2. the CPU was online before hibernation
                 */
		if (!cpu_online(0))
			_debug_hotplug_cpu(0, 1);
		break;
	case PM_POST_RESTORE:
		/*
                 * When a resume really happens, this code won't be called.
                 *
                 * This code is called only when user space hibernation software
                 * prepares for snapshot device during boot time. So we just
                 * call _debug_hotplug_cpu() to restore to CPU0's state prior to
                 * preparing the snapshot device.
                 *
                 * This works for normal boot case in our CPU0 hotplug debug
                 * mode, i.e. CPU0 is offline and user mode hibernation
                 * software initializes during boot time.
                 *
                 * If CPU0 is online and user application accesses snapshot
                 * device after boot time, this will offline CPU0 and user may
                 * see different CPU0 state before and after accessing
                 * the snapshot device. But hopefully this is not a case when
                 * user debugging CPU0 hotplug. Even if users hit this case,
                 * they can easily online CPU0 back.
                 *
                 * To simplify this debug code, we only consider normal boot
                 * case. Otherwise we need to remember CPU0's state and restore
                 * to that state and resolve racy conditions etc.
                 */
		_debug_hotplug_cpu(0, 0);
		break;
#endif
	default:
		break;
	}
	return notifier_from_errno(ret);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
fenghua yu
fenghua yu
87
100.00%
2
100.00%
Total
87
100.00%
2
100.00%



static int __init bsp_pm_check_init(void)
{
	/*
         * Set this bsp_pm_callback as lower priority than
         * cpu_hotplug_pm_callback. So cpu_hotplug_pm_callback will be called
         * earlier to disable cpu hotplug before bsp online check.
         */
	pm_notifier(bsp_pm_callback, -INT_MAX);
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
fenghua yu
fenghua yu
21
100.00%
1
100.00%
Total
21
100.00%
1
100.00%


core_initcall(bsp_pm_check_init);



static int msr_init_context(const u32 *msr_id, const int total_num)
{
	int i = 0;
	struct saved_msr *msr_array;

	if (saved_context.saved_msrs.array || saved_context.saved_msrs.num > 0) {
		pr_err("x86/pm: MSR quirk already applied, please check your DMI match table.\n");
		return -EINVAL;
	}

	msr_array = kmalloc_array(total_num, sizeof(struct saved_msr), GFP_KERNEL);
	if (!msr_array) {
		pr_err("x86/pm: Can not allocate memory to save/restore MSRs during suspend.\n");
		return -ENOMEM;
	}

	for (i = 0; i < total_num; i++) {
		msr_array[i].info.msr_no	= msr_id[i];
		msr_array[i].valid		= false;
		msr_array[i].info.reg.q		= 0;
	}
	saved_context.saved_msrs.num	= total_num;
	saved_context.saved_msrs.array	= msr_array;

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
chen yu
chen yu
153
100.00%
1
100.00%
Total
153
100.00%
1
100.00%

/*
 * The following section is a quirk framework for problematic BIOSen:
 * Sometimes MSRs are modified by the BIOSen after suspended to
 * RAM, this might cause unexpected behavior after wakeup.
 * Thus we save/restore these specified MSRs across suspend/resume
 * in order to work around it.
 *
 * For any further problematic BIOSen/platforms,
 * please add your own function similar to msr_initialize_bdw.
 */


static int msr_initialize_bdw(const struct dmi_system_id *d)
{
	/* Add any extra MSR ids into this array. */
	u32 bdw_msr_id[] = { MSR_IA32_THERM_CONTROL };

	pr_info("x86/pm: %s detected, MSR saving is needed during suspending.\n", d->ident);
	return msr_init_context(bdw_msr_id, ARRAY_SIZE(bdw_msr_id));
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
chen yu
chen yu
41
100.00%
1
100.00%
Total
41
100.00%
1
100.00%


static struct dmi_system_id msr_save_dmi_table[] = {
	{
	 .callback = msr_initialize_bdw,
	 .ident = "BROADWELL BDX_EP",
	 .matches = {
		DMI_MATCH(DMI_PRODUCT_NAME, "GRANTLEY"),
		DMI_MATCH(DMI_PRODUCT_VERSION, "E63448-400"),
                },
        },
	{}
};



static int pm_check_save_msr(void)
{
	dmi_check_system(msr_save_dmi_table);
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
chen yu
chen yu
16
100.00%
1
100.00%
Total
16
100.00%
1
100.00%


device_initcall(pm_check_save_msr);
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
chen yu
chen yu
408
31.38%
1
3.45%
rafael j. wysocki
rafael j. wysocki
308
23.69%
1
3.45%
sergio luis
sergio luis
281
21.62%
4
13.79%
fenghua yu
fenghua yu
146
11.23%
2
6.90%
konrad rzeszutek wilk
konrad rzeszutek wilk
75
5.77%
2
6.90%
ondrej zary
ondrej zary
30
2.31%
1
3.45%
andy lutomirski
andy lutomirski
11
0.85%
3
10.34%
marcelo tosatti
marcelo tosatti
7
0.54%
2
6.90%
suresh siddha
suresh siddha
6
0.46%
3
10.34%
ingo molnar
ingo molnar
6
0.46%
2
6.90%
stephane eranian
stephane eranian
6
0.46%
1
3.45%
andi kleen
andi kleen
4
0.31%
1
3.45%
k.prasad
k.prasad
3
0.23%
1
3.45%
paul gortmaker
paul gortmaker
3
0.23%
1
3.45%
linus torvalds
linus torvalds
2
0.15%
1
3.45%
steven rostedt
steven rostedt
2
0.15%
1
3.45%
pavel machek
pavel machek
1
0.08%
1
3.45%
magnus damm
magnus damm
1
0.08%
1
3.45%
Total
1300
100.00%
29
100.00%
  
Directory: arch/x86/power

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.